Convertible billing and reply envelope



May 19, 1964 D. T. scHUMAcHER CONVERTIBLE BILLING AND REPLY ENvELoPE 3 Sheets-Sheet 1 Filed June 26, 1963 IFJ/ro. I.

..-----iniez INVENTOR. DHV/D SCHUMACHEE rroeA/EY.

May 19, 1954 D. T. scHUMAcHI-:R 3,133,752

coNvERTIBLE BILLING AND REPLY ENvELoPE Filed June 26, 1963 5 Sheets-Sheet 2 [20 P/IG. 52 [ai a Las 39 (28 27' 8 37 Pa" [gfzfz /ZO l @m d 16.13. fo ,4

er la@ 14 Q 5 EJDS o Swu, A E i' Q L v INVENTOIL S m IZ 'VI' DAV/D 7: SCHUMHc/E/e rno Y l2 12 3 l B .I g E Lw May 19, 1954 D. T. scHuMAcHER 3,133,752

` CONVERTIBLE BILLING AND REPLY ENVELOFE Filed June 26, 1963 3 Sheets-Sheet 3 Ffa. l]

INVENTOR HA W0 ZJ SCHUMQCf/Ee rroeA/Ex United States Patent O 3,133,752 CNVERTWLE BRLING AND REPLY ENVELOPE David T. Schumacher, 1612 Strand, Hermnsa Beach, Calif. Filed .lune 26, 1963, Ser. No. 290,796 7 Claims. (Cl. 282-25) This invention relates to a `billing envelope which is convertible by the recipient into a reply envelope for use in mailing back a check to the sender.

A principal object of the invention is to provide such a convertible billing and reply envelope which is an irnprovement upon the envelope disclosed in my copending application Serial No. 137,855 led September 13, 1961, for U.S. Letters Patent upon a Convertible Billing En'- velope With Carbons for Preparing Statement and Customers Address in Duplicate, now VPatent 3,111,336 issued November 19, 1963.

The customers address in -duplicate was required in my prior invention aforesaid in order to provide this address where it is visible from outside the envelope as prepared at the point of origin for mailing to the customer, while at the same time incorporating the customers address at the point of origin with that portion of the original envelope which is to be converted into a reply envelope, in order that the biller, on receiving back the reply envelope, may credit this particular customer with any payment enclosed in the reply envelope.

It is an object of the present invention to provide a convertible billing and reply envelope in which the functions performed in said prior invention by preparing the customers address in duplicate are both performed without the necessity of preparing said address in duplicate, thereby eliminating the carbon required in said prior invention for preparing said address in duplicate.

Typing the statement and customers address when originally preparing the envelope of my prior invention required two separate introductions of the envelope into the typewriter, one to type the statement, and the other, to type the customers address.

Another object of the present invention is to provide a convertible billing and reply envelope wherein the statement and cuostorners address are both typed during a single insertion of the envelope into the typewriter, thus reducing the time and labor required to prepare the envelope for its original mailing.

While it is thus an object of the present invention to eliminate one of the carbons required in my aforesaid prior invention without loss of any of its essential functions so that the envelope of my present invention performs substantially the same functions as said prior invention and at a lower cost, it is a further object of the present invention to provide a convertible billing and reply envelope performing the same functions as aforesaid without requiring any carbon paper whatever.

Still another object of the present invention is to provide a convertible billing and reply envelope wherein the statement and customers address are both typed during a single insertion of the envelope into the typewriter while at the same time making a file copy for the original sender of said statement and address.

A yet funther object of the present invention is to provide such a convertible billing and reply envelope as last aforestated without requiring any carbon paper Whatever.

The elimination of carbon paper in the present invention is accomplished by manufacturing said envelope of a sheet of paper one surface of which has been coated by an acid clay-like material and the other surface of which has been coated with microscopic capsules carrying a colorless color reactant which turns to a colored form on contact with said acid clay-like material. For a full disclosure of the aforesaid coatings reference is made to U.S. Patents Nos. 2,641,557, 2,712,507 and 2,730,456.

The principle by which said coatings operate is illustrated when a paper surface coated with the capsules is placed in contact with a paper surface coated with acid clay-like material and then pressure is applied to the overlying sheet of paper as by writing or typing on said sheet, so as to rupture said capsules and release the liquid confined therein which thereupon contact the aci-d clay-like material on the underlying sheet which turns said liquid to colored form and produces the equivalent of a carbon copy on the sheet coated with acid clay-like material of whatever was written or typed on the overlying sheet of paper.

Another object of the present invention is to provide a convertible envelope as aforesaid which is made of doublecoated paper embodying the above noted copying principle which will produce a copy of the message written on said envelope at the saine time the latter is inserted in a typewriter to type the address thereon, and wherein said envelope provides means for refolding the same after it is taken `from the typewriter which will prepare the envelope -for its initial mailing, said folding bringing only like coated surfaces into contact thereby preventing pressure applied to the outside of the envelope during its initial mailing from producing marks on the interior thereof.

An additional object of the invention is in the folding of said sheet of double-coated paper when the latter is used in making said envelope so that like-coated surfaces are juxtaposed within the pocket of the envelope for receiving enclosures such as checks and money which may be placed therein for transmittal to the original sender when said envelope is reconstituted and mailed back to him, whereby the enclosures will not be subject to being inadvertently marked during said second mailing.

The manner of accomplishing the foregoing objects as well as further objects and advantages will be made manifest in the following description taken in connection with the accompanying drawings in which FIG. 1 is a diagrammatic plan view of a preferred embodiment of the envelope of the invention, as manufactured, with the pocket of the envelope placed downwar-dly against the desk and the primary flap unfolded along its transverse middle fold therein so that the primary and secondary flaps of the envelope and the narrow gurnmed tertiary ap thereof are extended full length from said pocket.

FIG. 2 is a bottom plan view of the envelope shown in FIG. 1.

FIG. 3 is a plan view of said envelope with the outer half of the primary llap and the secondary flap and tentiary yflap swung upwardly about the transverse middle fold in the primary flap so as to lower the secondary ilap into true overlapping relation with the upper wall of said envelope pocket.

FIG. 4 is a fragmentary enlarged sectional view taken on the line 4-4 of FIG. 1.

FIG. 5 is an enlarged diagrammatic cross sectional View taken on the line 5-5 of FIG. 1.

FIG. 6 is an enlarged diagrammatic cross sectional view taken on the line 6-6 of FIG. 3.

FIG. 7 is a plan view of the mailing face of the envelope of the invention after this has been fully prepared by the original sender for mailing to the addressee, and is taken in the direction of the horizontal line 7-7 of FIG. 8.

FIG. 8 is an enlarged diagrammatic cross sectional view taken on the line 8 3 of FIG. 7.

FIG. 9 is a view similar to FIG. 7 and illustrates what happens when the envelope is received by the addressee, the adhesion broken between a tertiary flap and the primary ap of the envelope, and when the secondary flap is unfolded outwardly from over the envelope pocket and pulled to tear it from the primary flap along the line of perforations where these two flaps are connected.

FIG. 10 is an enlarged diagrammatic cross sectional view taken on the line 10-10 of FIG. 9.

FIG. 1l is a plan view of the envelope of the invention after this has been reconstituted by the addressee for remailing to the original sender and with the rear envelope pocket wall turned upwardly showing the address of the original sender in large type printed thereon and the stamp for remailing the envelope to the original sender.

FIG. 12 is an enlarged diagrammatic cross sectional View taken on the line 12-12 of FIG. 11.

FIG. 13 is a perspective view of the envelope of this invention with the parts thereof extended as shown in FIG. l, when this envelope is made of paper coated in such a manner that no carbon paper is required by said envelope.

FIG. 14 is an enlarged diagrammatic longitudinal cross sectional view taken on the line 14--14 of FIG. 13 and illustrating how diverse coatings on opposite faces of the sheet of paper from which said envelope is made eliminates the need of carbon paper in making a copy of the message written on said envelope by the original sender thereof.

FIG. 15 is a perspective view of the modied form of envelope shown in FIGS. 13 and 14 with an insert sheet associated with said envelope in such a manner that a le copy of said message may also be made by the original sender of said envelope at the same time the latter is placed in a typewriter for typing the message and address thereon.

FIG. 16 is a perspective View of the insert sheet of the envelope shown in FIG. 15.

FIG. 17 is an exploded perspective view showing the envelope of the invention folded as shown in FIG. 3 prior to the typing of the message and address thereon and with two alternative form of le copy sheets one of which overlies said envelope and the other of which underlies said envelope and which may be placed in the typewriter at the same time with said envelope when typing the message and address on the latter and which will also produce a file copy of said message and address for the original sender of the letter.

Referring specifically to the drawings and particularly to FIGS. 1 to 12 inclusive, these depict a convertible envelope 20 which is an illustrative embodiment of the present invention and includes a sheet of paper 21 having transverse creases 22, 23, 24 and 25 which divide said sheet into front and back envelope pocket walls 26 and 27 respectively, a primary envelope flap 28, a secondary envelope ap 29, and a tertiary adhesive flap 30. Formed integral with the back pocket wall 27 are narrow laterally extending flaps which extend inside and are glued to adjacent portions of front pocket wall 26 to unite said pocket walls and produce an envelope pocket 36.

The upper face of front pocket wall 26 is preferably provided with a strip of dry adhesive 37 applied thereto adjacent the bend 22 in sheet 21. Attached lightly, as by spots of adhesive, to the upper surface of pocket wall 26 so as to overlie about one-half of said wall adjacent one end thereof is a patch of carbon paper 38, the carbon face of which is turned downwardly.

In addition to the creases above noted in the sheet of paper 21 the latter has a transverse crease 39 formed therein which is located lengthwise of and midway between the transverse edges of primary flap 23. Sheet 21 is also provided with a line of perforations 4t) along the crease 24 in said sheet for use by the addressee in separating secondary flap 29 from primary flap 28.

Formed in secondary flap 29 along its transverse medial axis is an elongated hole 41 through which the address of the addressee may be written on the outside face of front pocket wall 26 with its secondary flap in one position thereover and through which said address may be viewed when the envelope 20 is prepared for its initial mailing, with the secondary flap 29 in a reversed position relative to said front pocket wall. The face of secondary lap 29 which is exposed when the envelope 2) is so prepared for its initial mailing has the address of the original sender printed in small type adjacent crease 25 of sheet 21. The reverse face of secondary flap 29, which is concealed when the envelope 2) is prepared for its initial mailing, has a statement form 42 printed for a use to be made clear hereinafter.

The tertiary flap 30 has a small spot of adhesive 43 which is used to close the envelope when it is prepared for initial mailing. As may be seen in FIG. 2, the outside face of back pocket wall 27 has the address of the rst sender of the envelope 20 printed thereon in large type and also has a space provided thereabove for receiving a stamp for use in the second mailing of the envelope.

Operation The envelopes 20 are manufactured as shown in FIGS.

secondary flap 29 superimposed upon the front pocket wall 26 before being packaged for merchandising. As illustrated in the drawings, the envelope 20 is provided primarily for billing customers where the statement rendered consists of only a few brief items. The statement form 42 is thus ample in size for receiving the details of the statement to be submitted by way of the envelope 20. To type up an envelope 2t) to render such a statement to a given customer, who is the addressee, the typist picks up one of the envelopes 20 with this folded as packaged and above described, and inserts the edge of the folded envelope at the crease 39 thereof into the typewriter and, with one such insertion, types the date required for the statement and the address of the addressee as illustrated in FIG. 3. This completed, the typist removes the folded envelope 26 from the typewriter, ilips up the secondary flap 29 and the adjacent half of the primary flap 2S about the crease 39, tears out discards the carbon paper patch 37, and then wraps the flaps 2S, 29 and 30 about the transverse crease 24 to bring the secondary flap into reversely overlapping relation with the front pocket wall 26, meistens the adhesive spot 43 on the tertiary ap 3i) and bends the latter downwardly over the portion of the primary flap 28 adjacent the fold line 24 so as to complete the preparation of the envelope 2t) as shown in FIGS. 7 and 8 for its initial mailing. The address viewing hole 41 in the secondary ap 29 is here located in the same centralized position over the area for writing the address of the addressee on front pocket wall 26 so that the address previously written on this wall is now clearly visible through said hole. A stamp is now placed in the rectangle provided for this on the outwardly turned face of the secondary ilap 29 and the envelope is placed in the mail.

Upon the envelope being received by the addressee, the adhesive spot 43 is pulled loose from the outwardly disposed face of the primary flap 28, the primary and tertiary flaps are unfolded about the line of perforations 40 at the transverse crease 24 of the sheet of paper 21, and the secondary flap 29 is torn from the primary ilap along said line of perforations as shown in FIG. 9. The Secondary flap thus torn off of the envelope and the statement transmitted thereon is retained by the addressee as a part of his records of the billing, and his check in payment of the bill is slipped inside the envelope pocket 36, the strip of adhesive 37 is moistened, the primary flap is swung about the line of crease 24 into overlying relation with the front pocket wall 26 and pressed down onto the moistened adhesive 37 so as to seal the primary ap in closing relation with the pocket 36. A stamp is now applied to the rectangle for locating its position on the outer surface of the back pocket wall 27 and the envelope has been completely converted to a reply envelope and is ready for remailing to the first sender of the envelope whose address is pirnted on the outer face of said back pocket wall.

When the converted envelope 2t) is received back by its first sender, he may separate the primary Hap with a letter opener along the line of the crease 39 formed therein so as to unseal the envelope and remove the contents of the envelope pocket 36. When he does this, he is able toidentify the enclosures with the person sending the same because the name and address of the original addressee appears on the outer surface of the front pocket wall 26 as shown in FIG. 9 together with the details of the statement sent to said addressee in said envelope as it was originally mailed. The original sender of the envelope is thus able to correctly credit the specific addressee involved in this transaction for any payments made by him in the reconstituted envelope 20.

From the foregoing description, it is readily seen that the envelope 2th of the present invention possesses significant advantages over the convertible envelope shown in my copending application above referred to, in that only a single patch of carbon paper 3d is required in envelope Ztl and, in that only a single insertion into a typewriter is required in preparing the envelope 2i) for its initial mailing.

Reference is now made to FIGS. 13, 14, and 16 which illustrate a modied form of envelope 50 of the present invention which is exactly like the convertible envelope 2@ in general mode of operation excepting for certain differences which will now be pointed out. Envelope 59 performs all the functions of envelope Ztl but does not require the use of any carbon paper whatsoever. This is accomplished by making the envelope Sti of a sheet of paper 5f having its inner face coated with a coating 52 containing microscopic capsules present in such number that they are in substantial contiguity said capsules being relatively fragile and confining therein a water-immiscible oil vehicle in which is carried a colorless color reactant which turns to a colored form on contact with an acid clay-like material.

The outer face of sheet of paper 51 is provided with a coating 53 which embodies acid clay-like material. Thus when a section of sheet 51 is placed against another section of said sheet so that the coating 52 on the first section of said sheet engages the coating 53 on the secon-dnsecton of said sheet, and pressure is applied to the superimposed section of said sheet such as by writing or typing thereon, the capsules in coating 52 are ruptured allowing the oil vehicle within said capsules to escape so that the colored reactant carried thereby contacts the acid clay-like material in coating 53 and produces a color in the areas subjected to such writing or typing so as to produce a copy in the coating S3 of the writing or typing above referred to. For specific examples of the materials thus briefly described as being included in coatings 52 and 53 of the sheet of paper Si, reference is made to the U.S. patents referred to hereinabove.

When referring to features of the convertible envelope Sil which are identical with like features on the convertible envelope Zti, corresponding reference numerals will be employed as were used in describing the latter, with prime attached.

Convertible envelope 50 is prepared for its initial mailing and then converted for its second mailing in identically the same way as already described for a convertible envelope 26 with the exception of the fact that envelope Si) has no carbon paper associated therewith so that it is unnecessary to remove and dispose of carbon paper as is the case in handling the envelope 20. It is further desired to call attention to the fact that the envelope 50 possesses a distinct advantage in that while use is made of this double-coated paper to furnish the equivalent of a carbon copy on the outer face of front pocket wall 26 when preparing the envelope for its initial mailing, the completion of this preparation which results in the various parts of the envelope being positioned as shown in FIG. 8, results in practically all portions of the coating S2 on a sheet of paper 51 being in face-to-face contact with other portions of the same coating or they are exposed outwardly where they cannot come in contact with any portion of the coating 53 on said sheet of paper and thus permit any of the hidden surfaces on the sheet of paper Si being inadvertently marked upon by the application of pressure to the exterior of the envelope during its initial mailing. There is one unimportant exception to the statement above made where the tertiary adhesive flap Sti overlies a narrow marginal area of the outwardly exposed face of primary flap 2S. Any inadvertent marking which is thus applied to this marginal portion of the blank through the outwardly exposed face of primary flap 2S will be seen to be of relatively no consequence.

When the envelope Sil is converted for its second mailing, the inner face of primary ap 2S covered by coating 52 is applied to the outwardly exposed face of front pocket Wall 26 which is covered by coating 53 so that on the return mailing of the envelope there is a possibility of marks being inadvertently made through the primary Hap 28 onto the front pocket Wall 26 which carries the address of the addressee and the copy of the specific details of the bill rendered by this envelope. In the ordinary handling of mail, there is little likelihood that the outer face of front wall 26 would be subjected to suiicient inadvertent markings from this cause as to render the information carried on this surface illegible.

Checks, money and the like enclosed within the envelope pocket 36 of envelope 5t) are free from being inadvertently marked by juxtaposition of the coatings 52 and 53 adjacent said enclosures because the inner faces of both said front and back pocket walls 26 and 27 are covered by the coating 52.

The present invention also makes provision for the preparation of a file copy for the original sender of either of envelopes 2f) or 50 at the time said envelope is inserted into the typewriter to prepare this for its initial mailing. FIGS. 15 and 16 illustrate the manner of doing this for envelope 50. An insert sheet 54 of the same kind of coated paper as sheet 51 and of a proper size to be inserted into the envelope 50 as shown in FIG. l5 is provided as a part of envelope 50 wherever this service is required. Thus envelopes 50 are manufactured with the insert sheets 54 inserted therein as shown in FIG. l5 and each envelope 5ft when taken out of its package has such an insert sheet already inserted in place therein for use in preparing the envelope and a separate file copy thereof for the original sender with one insertion of the envelope into a typewriter. The upward turned surface of sheet 54 as seen in FIGS. 15 and 16 is covered by coating 53 and the downturned face of insert sheet 54 is covered by coating 52.

Thus when the envelope 50, embodying the insert sheet 54, is inserted in a typewriter and the address of the addressee is typed on the upwardly exposed face of insert sheet 54 where this is visible through hole 4l', the impact of this typing on sheet 54 is transmitted through the 4 coating 52 on the lower face thereof to the coating 53 on the outer face of front pocket wall 26 of said envelope thereby printing a true copy of said address on said front pocket wall. When, in the same insertion in the typewriter, the details of the statement are typed in the statement form 42' provided on the outwardly exposed face of secondary hap 29 as shown in FIG. 15, the coating 52 on the lower surface of this flap receives the impact of said typing and thus transmits to the coating 53 on the upwardly exposed surface of the insert sheet 54 a true copy of said statement details. In likemanner the impact of this typing is transmitted through insert sheet 54 to the coating 52 provided on the lower surface thereof which is thus caused to transmit to the coating S3 on the outwardly exposed face of front pocket wall 28 a second copy of said statement details.

It is thus seen that there is no general change in the mode of operation of typing all the data necessary on convertible envelope 59 in a single insertion of the latter into a typewriter and preparing this envelope for its initial mailing and at the same time providing a le copy of the data so typed for preservation in the files of the original sender of the envelope. T he insert sheet d after the envelope 5) has thus been typed up readily slips from the balance of the envelope and is placed in the original senders fiies while the folding of the envelope is completed in the same manner as aforedescribed for envelope to complete this envelope for its initial mailing.

Alternative forms of accessory record sheets for use with either of the envelopes 20 or 50 of the invention are illustrated in FIG. 17. These modifications include an overlay sheet 5S which is shown in superimposed relation with a convertible envelope 20, the sheet 55 being of the same size as insert sheet 54 and made of ordinary paper and being provided with a patch of carbon paper 56 which is lightly attached by spots of adhesive to the lower face of sheet 55 with the carbon face thereof turned downwardly, said patch being of suiicient size as to cover both the area of hole 41 as well as the statement form d2 on the envelope 20. When the overlay sheet 55 is employed in association with a convertible envelope Z0, it is laid directly on top of the latter and this sheet is provided with a printed outline 57 of hole 41 and an outline 58 of statement form 42 so that these outlines are directly superimposed over said hole and statement form when the sheet 55 correctly overlies the envelope 2h. When the sheet 55 and envelope 20 are thus assembled, they are inserted into the typewriter together after which the details of the statement are typed in the outline 58 on the overlay sheet 55 and the address of the addressee is typed within the outline 57 of the hole 41 of said envelope. The overlay sheet 55 is thus provided with a ribbon copy of the data typed on envelope 20 while a carbon copy of the address is applied to the front pocket wall 26 while carbon copies of the statement data are applied to the upturned faces of both the secondary flap 29 and the front pocket wall 26. The patch of carbon paper 56 is of course detached from overlay sheet 55 and discarded before tiling said overlay sheet.

Also shown in FIG. 17 is an underlay sheet S shown as underlying a convertible envelope 2@ in direct superimposed relation therewith. This underlay sheet being of the same size and kind of paper as the overlay sheet 55 and has a patch of carbon paper 6i) lightly attached by spots of glue to the upper surface thereof said patch having the carbon thereof facing downwardly and being of the same size and similarly located relative to underlay sheet 59 as the patch of carbon paper 56 is relative to overlay sheet 55. When using underlay sheet 59 in conjunction with convertible envelope 20, the latter is superimposed above said sheet and the two are inserted in a typewriter together after which the typing above described which is done on envelope 20 to prepare this for its initial mailing is completed with one insertion into the typewriter, and a carbon copy of the matter thus typed on the convertible envelope 20 is transferred by carbon paper 60 onto the underlay sheet 59. Thus when the convertible envelope 20 and underlay sheet 59 are removed from the typewriter, the patch of carbon paper 60 is immediately detached and discarded and the sheet 59 bearing the record thus taken from envelope 2% is piaceri in the files of the original sender of said envelope.

The claims are:

l. A convertible envelope provided to be mailed by ane original sender to an addressee for transmitting a message requiring ia reply, said envelope comprising: a sheet of paper transversely creased to divide said sheet into the following elements arranged consecutively, a front en- 'velope pocket wall, a back envelope pocket wall, a primary envelope closing flap, and a secondary envelope closing flap said pocket walls being connected together along their lateral edges to form an envelope pocket said primary flap also having a transverse `fold bisecting area of said ap and causing said primary ap to be folded forwardly upon itself to invert said secondary ap and superimpose it upon said front pocket wall, said secondary iiap having a hole through which the address of the addressee may be written within a certain area on said front pocket wall exposed through said hole; pressure sensitive copying means responsive to pressure applied to the upwardly exposed surface of said secondary ap in writing or typing a message thereon to produce a copy of said message directly therebeneath on said front pocket wall; means for holding said secondary flap in closing relation with said pocket when said two flaps are wound backwardly around said pocket for the initial mailing of said envelope thereby hiding said message and the copy thereof while exposing said address to view through said hole; and means for holding said primary flap in closing relation with said pocket when folded forwardly against said front pocket wall after said secondary flap has been separated from said primary flap by the addressee for the return mailing of said envelope.

2. A convertible envelope as recited in claim l wherein a gummed tertiary ap is also provided by said sheet of paper for securing the outer edge of said secondary flap to said primary flap to hold said secondary hap in closing relation with said pocket during said initial mailing.

3. A convertible envelope las recited in claim l wherein the surface of said sheet of paper on which said message is written and on which the copy thereof is to be produced is coated with `an activating agent for producing marks on said surface when contacted by a second normally clear agent and wherein the opposite surface of said sheet of paper is provided with a coating embodying minute sealed capsules of said second agent, whereby writing or typing a message on the upwardly exposed face `of said secondary ap when the latter is initially inverted in superimposed relation with said front pocket wall will rupture said capsules and produce a copy of said message on the upturned face of said pocket wall, said coatings comprising said pressure sensitive copying means.

4. A convertible envelope as recited in claim 3 wherein said envelope in its original form includes an insert sheet inserted between said front pocket wall and said secondary envelope flap, said insert sheet having its upper surface provided with a coating like said first mentioned coating and its bottom surface is provided with a coating like said subsequently mentioned coating `whereby a copy Iwill be received on said insert sheet of the message written or typed on said secondary ap and wherein said address may be written or typed on said secondary ilap and wherein lsaid address may be written or typed within said hole directly on said insert sheet and copies of said message rand said address will be transmitted by said insert sheet onto said front pocket wall.

5. A convertible envelope as recited in claim 1 wherein said pressure sensitive manifold copying means comprises a sheet of carbon paper lightly secured to said front pocket wvall and coextensive in its dimensions with the 4area provided on said secondary ap for receiving said message.

6. A convertible envelope as recited in claim 1 wherein said envelope in its original folded form includes an overlay tile copy sheet of paper of approximately the same dimensions as the folded envelope and `overlying the same, said overlay sheet having the outline of said hole and an outline of said message space printed thereon and being provided `with a patch of carbon paper lightly secured to the bottom of said overlay sheet the carbon facing downwardly `and underlying the areas of said outlines.

7. A convertible envelope as recited in claim 1 wherein said envelope in its original folded form includes an underlay hle copy sheet of paper of approximately the same dimensions as the folded envelope and underlying the sarne and a patch of carbon paper lightly secured to the top of said underlay sheet with the carbon paper 10 facing downward and underlying the area of said hole, and the area within which said message is to be written.

References Cited in the le of this patent UNITED STATES PATENTS 2,15 6,142 Blitz Apr. 25, 1939 2,303,992 lGardner Nov. 24, 1942 2,669,464 Lay Feb. 16, 1954 2,976,062 Breohner Mar. 21, 19611 31,048,426 Rodriguez Aug. 7, 1962 3,111,336 Schumacher Nov. 19, 1963 

1. A CONVERTIBLE ENVELOPE PROVIDED TO BE MAILED BY AN ORIGINAL SENDER TO AN ADDRESSEE FOR TRANSMITTING A MESSAGE REQUIRING A REPLY, SAID ENVELOPE COMPRISING: A SHEET OF PAPER TRANSVERSELY CREASED TO DIVIDE SAID SHEET INTO THE FOLLOWING ELEMENTS ARRANGED CONSECUTIVELY, A FRONT ENVELOPE POCKET WALL, A BACK ENVELOPE POCKET WALL, A PRIMARY ENVELOPE CLOSING FLAP, AND A SECONDARY ENVELOPE CLOSING FLAP SAID POCKET WALLS BEING CONNECTED TOGETHER ALONG THEIR LATERAL EDGES TO FORM AN ENVELOPE POCKET SAID PRIMARY FLAP ALSO HAVING A TRANSVERSE FOLD BISECTING AREA OF SAID FLAP AND CAUSING SAID PRIMARY FLAP TO BE FOLDED FORWARDLY UPON ITSELF TO INVERT SAID SECONDARY FLAP AND SUPERIMPOSE IT UPON SAID FRONT POCKET WALL, SAID SECONDARY FLAP HAVING A HOLE THROUGH WHICH THE ADDRESS OF THE ADDRESSEE MAY BE WRITTEN WITHIN A CERTAIN AREA ON SAID FRONT POCKET WALL EXPOSED THROUGH SAID HOLE; PRESSURE SENSITIVE COPYING MEANS RESPONSIVE TO PRESSURE APPLIED TO THE UPWARDLY EXPOSED SURFACE OF SAID SECONDARY FLAP IN WRITING OR TYPING A MESSAGE THEREON TO PRODUCE A COPY OF SAID MESSAGE DIRECTLY THEREBENEATH ON SAID FRONT POCKET WALL; MEANS FOR HOLDING SAID SECONDARY FLAP IN CLOSING RELATION WITH SAID POCKET WHEN SAID TWO FLAPS ARE WOUND BACKWARDLY AROUND SAID POCKET FOR THE INITIAL MAILING OF SAID ENVELOPE THEREBY HIDING SAID MESSAGE AND THE COPY THEREOF WHILE EXPOSING SAID ADDRESS TO VIEW THROUGH SAID HOLE; AND MEANS FOR HOLDING SAID PRIMARY FLAP IN CLOSING RELATION WITH SAID POCKET WHEN FOLDED FORWARDLY AGAINST SAID FRONT POCKET WALL AFTER SAID SECONDARY FLAP HAS BEEN SEPARATED FROM SAID PRIMARY FLAP BY THE ADDRESSEE FOR THE RETURN MAILING OF SAID ENVELOPE. 